Process and apparatus for making brazed joints.



F. W. HEUSER.

PROCESS AND APPARATUS FOR MAKING BRAZED JOINTS.

APPLICATION hLED FEB. 6, 1914- Patented Jan. 25, 1916.

a: ZIJIVB H 101 Afiorne 1's UNITED STATES PATENT OFFICE.

ramnnrcn wrmmnu Banana, or GROSS-LICHTERFELDE, Nana BERLIN, onmramr.

rnocss's mnmm'rus For. MAKING rsaznn JOINTfiEIQ spen Toall whom it mayconcem.

Be it known that I, FRIEDRICH WiLrmLM Hansen, a subject of the German Emeror,-

, by means of whichbrazed joints of high guaiizy as regards security ofjoint are prouc A further object of my invention is to provide a methodby which, in the making of secure joints as above,-the brazing and the--melting of brazing material is confined closely to the line alongwhich the articles are to be united. g A further object of my-inventionis to provide an apparatus by means of which the 1 process herein to bedescribed may be effectively carried out.

Other objects will appear as the specifica- In the prior art the makingof brazed joints by use of the electric arc has been usual but thejoints produced have not been altogether satisfactory. According to. themethod generally employed the working carbon of the are, held by asuitable holder, has

been drawn by the operator along the line to be brazed, after thebrazing material has been placed between the articles along said line.Thejoint thus produced has, depending somewhat uponthe form of thearticles to be, brazed to ether, either had a poorly defined brazingo'cus or else required in or-' der to obtain a closely defined brazinglocus and to prevent the brazing material flowing away from the joint orseam over the article to be welded, the use of molds or forms ofchamotte, silicon carbid, carbon or iron.- The joints thus formed havebeen, generally,

either insecure or else deeply molten holes or channels havebeen'produced along the line of the same.

I have observed that insecure joints al-' ways result when the prolongedaxis of the I w'o'rking carbon instead of. intersecting the e'ndof thebrazing material to be melted intersects said brazing material at someother po i n't' 'in such cases the arc loses its concentrated pointedflame like aspect and splits up into a number of parts. The deeplymolteniholes or channels along the line of Specification of Letters latent.

Application filed February 8, 1914. serial Il'o. 816,908.

Patented Jan. 25, 1916.

of the subject matter of the present application, I hold the workingcarbon so that its prolonged axls always intersects the molten end ofthe brazing material, and draw the carbon while so melted alo'n the lineof the joint to be brazed at a spec conforming to the speed at wh1ch thebrazing material melts; this will be, in most cases, substantiallyuniform speed. Such process lendsv itself best to mechanicaloperationinasmuch as the necessary skill and care required to carry out theprocess manually is almost too muc to expect 7 of the average operator.

But even with suitable apparatus for hold-' ing and guiding the carbonas above, perfect omts will not be producedv unless some further meansbe provided for defining the seam, i. e., for confining the brazingmaterial to the line of separation between the articles to be united;and even if such defining means be the molds of the prior art (chamotte,silicon carbid, carbon or iron as above), the seams will notbethoroughly good. Under such conditions the are will 'be unstable aswill be evident by ocular inspection and its peculiar sound; the brazingwill not be uni form and the joint will not be good at all points. Ifind, however, through experiment, that if a mold of good heatconducting material be used the joint becomes uniform,

' arc does not tend to jump over upon the copper which, therefore,remains uninjured so that it may be used repeatedly; and after thebrazing is completed the copper form is easily removed.

In the accompanying drawing there is illustrated a preferred form ofapparatus which- Figure 1 represents a front elevation of for carryingout my improved process, in

said apparatus-and Fig. 2 a transverse section along the line 2-2 ofFig. 1.

In this drawing a worm a operated by handle d and supported in holders fis held at any elevation by set screws 6. A nut g, traveling upon theworm, carries a member It provided with a slot 71., and having at itsouter end. a cylindrical spindle i. A guide rod Z held laterallyadjustable in arms n enables the arm k to be set at any desired angle inthe yertical plane. The spindle 2' carries a clampin device 0 adjustablethereupon, in which isield the working carbon 0' which is therefore,adjustable so as .to have its axis take any desired direction.

The apparatus as a whole is placed upon the two pieces r and s which areto be unlted together b theplate g, and is held in position by camps tseparated by insulating material t from the pieces to be brazed. Astrip. of copper or other material of good heat conductivity u is placedon the plate q withits outer side, and the carbon properly adjusted sothat;. ;its'"axis will lie in a plane which includes the axis of thebrazing material. When the arc is struck the carbon should be adjustedin the just specified plane so that its prolonged axis will pass throughthe molten end of the brazing material and by turning the handled, thecarbon is then moved along at the desired uniform rate and its prolongedaxis will continue to intersect the end of the molten brazing material.Or thecarbon maybe moved along b causing the worm to be driven from asuitab e electric motor, the speed of which may be regulated.

The brazing material may be of any suitable substance. F or making railjoints, as set forth in the specification, I prefer that this materialbe something analogous to that of the rails themselves as, e. 9., steelor iron.

1. The method of brazing by use of'the electrio are which comprisesholding the working carbon so that its axis intersects, at all times,the molten end of the brazin materialand simultaneously moving sai bonin a direction parallel to the line of thejoint to be brazed while, atthe same time, rapidly absorbing) heat from portions of'the materials tobe razed which lie adjacent to the line'of the proposed joint.

The method of brazing by use of the carelectric are which comprisesholding the joint to be brazed while, at the same time,

arranging a strip of good heat conducting material adjacent to thematerials to be brazed and to the line of the proposed joint whereby thearc is stabilized and heat' is rapidly transferred to said heatconducting material. I

3. An apparatus for, producing brazed joints comprising, in combination,means for holding the working carbon at a definite anglewith respect tothe work, means for'moving-said carbon in a, direction parallel to theline of the joint, and means for rapidly absorbing heat from portions ofthe materials to be brazed which lie adjacent to the line of theproposed joint.

4. An apparatus for producing brazed joints comprising, in combination,means for holding the worklng carbon at a definite angle with respect tothe work, means for moving said carbon in a direction parallel to theline of the joint, and a strip of good heat conducting material adjacentto .the materials to be brazed and to the line of the proposed joint. I

5. An apparatus for producing brazed joints comprising, in combination,means for holding the working carbon at a definite angle with respect tothe work, means for movingsaid carbon -'in a direction parallel to theline of the joint, and a strip of copper adjacent to the materials to bebrazed and to the line of the proposed joint.

In testimony whereof, I have hereunto set my hand in the presence 'oftwo subscribing witnesses.

FRIEDRICH WILHELM HEUSER.

Witnesses \VQLDEMAR HAUr'r, HENRY Hasrna.

